A5050023964- Lipid Membrane Structure and Behavior
- T-cell and B-cell Immunology
- Monoclonal and Polyclonal Antibodies Research
- Immune Cell Function and Interaction
- Force Microscopy Techniques and Applications
- Cellular transport and secretion
- Advanced Fluorescence Microscopy Techniques
- Axon Guidance and Neuronal Signaling
- Protein Kinase Regulation and GTPase Signaling
- Cellular Mechanics and Interactions
- CAR-T cell therapy research
- Cell Adhesion Molecules Research
- Nanopore and Nanochannel Transport Studies
- Receptor Mechanisms and Signaling
- Advanced biosensing and bioanalysis techniques
- Immunotherapy and Immune Responses
- Spectroscopy and Quantum Chemical Studies
- Protein Structure and Dynamics
- RNA Research and Splicing
- Hippo pathway signaling and YAP/TAZ
- Microfluidic and Bio-sensing Technologies
- Advanced Biosensing Techniques and Applications
- Glycosylation and Glycoproteins Research
- RNA Interference and Gene Delivery
- Computational Drug Discovery Methods
University of California, Berkeley
2016-2025
QB3
2011-2025
Nanyang Technological University
2017-2025
Lawrence Berkeley National Laboratory
2012-2024
Berkeley College
2008-2024
Quantitative BioSciences
2022
Howard Hughes Medical Institute
2009-2020
Marine Biological Laboratory
2017-2020
National University of Singapore
2010-2019
Singapore-MIT Alliance for Research and Technology
2014
Lithographically patterned grids of photoresist, aluminum oxide, or gold on oxidized silicon substrates were used to partition supported lipid bilayers into micrometer-scale arrays isolated fluid membrane corrals. Fluorescently labeled lipids observed diffuse freely within each corral but confined by the micropatterned barriers. The concentrations fluorescent probe molecules in individual corrals altered selective photobleaching create patches with differing compositions. Application an...
The immunological synapse is a specialized cell-cell junction that defined by large-scale spatial patterns of receptors and signaling molecules yet remains largely enigmatic in terms formation function. We used supported bilayer membranes nanometer-scale structures fabricated onto the underlying substrate to impose geometric constraints on formation. Analysis resulting alternatively patterned synapses revealed causal relation between radial position T cell (TCRs) activity, with prolonged...
The guanine nucleotide exchange factor (GEF) Son of Sevenless (SOS) is a key Ras activator that autoinhibited in the cytosol and activates upon membrane recruitment. Autoinhibition release involves structural rearrangements protein at thus introduces delay between initial recruitment activation. In this study, we designed single-molecule assay to resolve time receptor-mediated initiation GEF activity individual SOS molecules on microarrays Ras-functionalized supported membranes....
Moving Signals Many types of human breast cancers overexpress a cell-surface receptor—EphA2—a tyrosine kinase activated by the ligand ephrin-A1 present on adjoining cells. Salaita et al. (p. 1380 ; see Perspective Paszek and Weaver ) studied regulation mechanically stimulated EphA2 signaling inducing intermembrane between living EphA2-expressing cancer cells supported membranes displaying laterally mobile ephrin-A1. When receptors engaged their ligands, they formed clusters that moved...
Engineering efficient, directional electronic communication between living and nonliving systems has the potential to combine unique characteristics of both materials for advanced biotechnological applications. However, cell membrane is designed by nature be an insulator, restricting flow charged species; therefore, introducing a biocompatible pathway transferring electrons across without disrupting significant challenge. Here we describe genetic strategy move intracellular inorganic...
Cell-cell recognition often requires the formation of a highly organized pattern receptor proteins (a synapse) in intercellular junction. Recent experiments [e.g., Monks, C. R. F., Freiberg, B. A., Kupfer, H., Sciaky, N. & A. (1998) Nature (London) 395, 82-86; Grakoui, Bromley, S. K., Sumen, C., Davis, M. M., Shaw, S., Allen, P. Dustin, L. (1999) Science 285, 221-227; and D. Chiu, I., Fassett, Cohen, G. B., Mandelboim, O. Strominger, J. Proc. Natl. Acad. Sci. USA 96, 15062-15067] vividly...
We present a simple and convenient method for creating fluid supported bilayers which contain oriented functional photosynthetic reaction centers (RCs). The are prepared by fusion of proteoliposomes with glass surface. spontaneous insertion RCs into preformed small, unilamellar vesicles. in these vesicles shown to be the cytochrome c binding surface on outside H-subunit facing inside. Upon surfaces, remain highly oriented, exposed bulk solution. at density order 10(11) RCs/cm2. quality lipid...
Cellular membranes exhibit a variety of controlled curvatures, with filopodia, microvilli, and mitotic cleavage furrows being only few many examples. Coupling between local curvature chemical composition in could provide means mechanically controlling the spatial organization membrane components. Although this concept has surfaced repeatedly over years, experimental investigations have proven elusive. Here, we introduce an platform, which microfabricated surfaces impose specific patterns...
The controlled addition of structurally defined components to live cell membranes can facilitate the molecular level analysis surface phenomena. Here we demonstrate that surfaces be engineered display synthetic bioactive polymers at densities by exogenous membrane insertion. were designed mimic native cell-surface mucin glycoproteins, which are their dense glycosylation patterns and rod-like structures. End-functionalization with a hydrophobic anchor permitted incorporation into cultured...
T cells discriminate between self and foreign antigenic peptides, displayed on antigen presenting cell surfaces, via the TCR. While molecular interactions TCR its ligands are well characterized in vitro, quantitative measurements of these living required to accurately resolve physical mechanisms signaling. We report direct single molecule triggering by agonist pMHC hybrid junctions live primary supported lipid membranes. Every pMHC:TCR complex over entire is tracked while simultaneously...
Nickel-chelating lipids are general tools for anchoring polyhistidine-tagged proteins to supported lipid bilayers (SLBs), but controversy exists over the stability of protein−lipid attachment. Here, we show that chelator suitable anchors building stable, biologically active surfaces a simple Langmuirian model is insufficient describe their behavior. Desorption kinetics from governed by valency surface binding: monovalently bound desorb within minutes (t1/2 ≈ 6 min), whereas polyvalently...
Significance Ras is a key signaling molecule in living cells, and mutations are involved 30% of human cancers. It becoming progressively more clear that the spatial arrangement proteins within cell, not just their chemical structure, an important aspect function. In this work, we use series quantitative physical techniques to map out tendency two molecules bind together form dimer on membrane surfaces. Insights from as well technical assays developed, may help discover new therapeutic drugs...
During antigen recognition by T cells, signaling molecules on the cell engage ligands antigen-presenting and organize into spatially distinctive patterns. These are collectively known as immunological synapse (IS). Causal relationships between large-scale spatial organization signal transduction have previously been established. Although it is that receptor transport during IS formation driven actin polymerization, mechanisms which different proteins become sorted remain unclear. sorting...